# Dermatosis Associated with Feeding Low-Quality Food (Generic Food Dermatosis): A Case Series

## TL;DR

This study reports 22 dogs with skin issues linked to low-quality food, showing improvement after switching to a better diet.

## Contribution

The study documents the ongoing occurrence of 'generic food dermatosis' in modern veterinary practice.

## Key findings

- Dogs fed low-quality food showed severe skin lesions and lethargy.
- Switching to high-quality food resolved symptoms within 15–30 days.
- Histopathology confirmed nutritional deficiency-related skin changes.

## Abstract

This study describes 22 dogs that developed severe dermatosis characterized by thick crusts, scaling, and symmetrical lesions on the face, mucocutaneous areas, and paws. All affected animals were exclusively fed low-quality commercial dog food. Histopathology in nine cases showed changes compatible with nutritional deficiencies, particularly marked parakeratotic hyperkeratosis and spongiosis. Other common causes of similar skin lesions, such as infections or autoimmune diseases, were ruled out. The aim of this work was to document this condition—similar to the “generic food dermatosis” first reported in the 1980s—and to demonstrate that it still occurs in clinical practice. After switching to a high-quality, nutritionally complete diet, all dogs improved rapidly: lethargy resolved within one week, and skin lesions healed within 15 to 30 days. This study shows that dermatosis associated with poor-quality diets remains present in some regions and should be considered in dogs with crusted, scaly lesions, especially when they are eating inexpensive, low-quality food. Awareness of this disease supports quicker diagnosis, prevents unnecessary treatments, and highlights the societal importance of access to balanced and nutritious diets for animal health.

Severe crusting dermatosis affecting the mucocutaneous junctions, pressure points, and trunk of dogs fed low-quality dry food was first reported in the United States in the 1980s. Since then, only a few cases have been documented. Twenty-two adult dogs owned by private individuals were evaluated. All dogs exhibited thick crusts forming plaques and marked scaling on the face—particularly around the lips, nasal bridge, and eyelids—as well as on the paw pads, dorsal digits, abdomen, and dorsum. Pruritus ranged from moderate to severe, and all dogs showed varying degrees of lethargy and reduced activity. Each dog was fed a low-quality commercial diet. A presumptive diagnosis of dermatosis associated with poor-quality food was made. Skin biopsies from nine dogs revealed similar histopathologic changes, characterized by epidermal hyperplasia, severe parakeratotic hyperkeratosis with spongiosis, and exocytosis of lymphocytes and neutrophils. The skin lesions resolved within 15–30 days after switching to a high-quality diet. This case series highlights that dermatosis associated with low-quality food should remain in the differential diagnosis for dogs presenting with symmetric crusted and scaly lesions on the face, mucocutaneous junctions, and paws, particularly when nutritional deficiencies are suspected.